Paper making



' Feb. 17, 1925; 4,526,553

L. KIRSCHBRAUN ET AL PA ER MAKING Filed Dec. 15, 1921 Patented Feb. 17, 1925.

UNITED STATES PATENT OFFICE.

Lnsrnit KIRSCHIBRAUN, or CHICAGO, ILLINOIS, AND THOMAS w. monsrg or RIDGE- FIELD raamnnw JERSEY; SAID MORSE assrenoa To FLINTKOTE oomramr, a

CORPORATION MASSACHUSETTS.

PAPER MAKING.

Application filed December 15,.1921. Serial 1T0. 522,691.

To all whom it may concern 1 Be it known :that we, LESTER KIRsoHsRAUN and THOMAS l/V. MOR SE, both citizens of the United States, vand residing, respectively, in the'city of Chicago, county of Cook, and ,State of Illinois, and in the town of Ridgefield Park, county of Bergen, and State of New Jersey, have invented certain new and useful Improvements in Paper Making, of p which the following is a specification.

This invention relates to improvements in paper making, and refers more particularly 1 to the manufacture. of awater-proof paper,

. in which the fibrous constituents of the sheet are made water-proof by means of, a waterproof agent, such as pitches, bitumens, paraffines, resins,.and the like. v The object of the invention is to produce a waterproof-paper, in which the paper is made water-proof simultaneously with the web-forming operation, as forrexample on i the usual multicylinder paper machine.

One of the present applicants, Lester Kirschbraun, has heretofore produced a- 5 water-proof paper by incorporating anonadhesive bituminous emulsion with the H- brous pulp during the web-forming operation on the paper machine. While such paper iswater proof against water in liquid phase, it is .less proof against moisture, as for example against the passage of air more or less saturated with water vapor. The present invention is, therefore, directed to the production of a I substantially air-tight paper, which is water-proof and partly moisture-proof. p a

The object of the present invention, therefore, is. to provide a novel product, process and apparatus for the production of water-v proof paper; It is a further object of the invention to obtain such result on the standard form of multicylinder paper machinery, and in a particularly effective and simple operation.

In carrying out the invention, we take advantage of the process heretofore invented by the applicant Lester Kirschbraun, in which a non-adhesive bituminous emulsion is made, in which the bitumen forms the internal phase of the emulsion, and is therefore capable of being mixed wit-h the fibrous p l and passed over the paper machinery without sticking to or clogging up the various elements of the machine.

Inasmuch as the manner of making the emulsion forms no part of the resent invention, it need not be describe in detail. Briefly, however, a non-adhesive emulsion suitable for use in the present invention may be made as follows:

To a suspension. of colloidal cla and water preferably in heated condition is added the water-proofing agent such as hot liquid asphalt of about 160 F. melting point with agitation and in such a' way as to form an effective non-adhesive emulsion in which the asphalt forms the internal phase. Instead of using colloidal clay, other emulsifying 'agents may be used, and instead of asphalt there may be usedotherhydro-carbons, such as paraflines, wax tailings, resins, coal tars, stearin pitches, and the like.

In its'broader aspects the invention contemplates the use of these other constituents. Also, in the more specific features of the invention we have found clay and asphalt to be highly desirable.

In' order to more clearly understand the invention, we show herewith a diagrammatic vertical sectional view of one apparatus in which the invention may be carried out.

Referring to the drawings, ldesignates a vat of a multicylinder papermachine, in which is mounted the usual cylinder mould 2 and couch roll 3. This vat is ada tedto contain a paper stock from which t e web is formed and carried on the under side of the blanket 4:. 5 designates a similar vat, containing cylinder mould 6. In the vat 5, and interposed between the bafile board 7 and mould 6, is an auxiliary vat 8, adapted to receive a non-adhesive emulsion of the character previously described. The emulsion passes out through the slot 9 on to a levelling board 10 adjustably mounted at 11, the arran ement being such that the emulsion is de ivered as close as possible to the periphery of the mould 6 but slightly below ward flow of the sto k by the board 10,

and this in turn tends to prevent an excess of say 500% of waterproofing agent to fibre, emulsion dropping down into the vat. the effect being the production'of substan- As the cylinder mould 6 rotates in the ditially a continuous non-porous film of birection shown by the arrows, a web of fi-v tumen or pitch as the web emerges from brous stock is first deposited on the mould, thevat; It must be observed that the emulas for example between the points a and b. sion by this process does not come in contact A small amount of the emulsion will become with either blankets or cylinder mold. mixed w h the stock locally, as for example i We claim as our invention:

between time points I) and 0, butasthe forma- 1. A process of making water-proof tion of the web approaches the point '0, inpaper, consisting in forming a plurality of creasingly greater-amounts of the emulsion fibrous webs on a paper machine, and apwill be present with the 'stock, until finally, plying to one of said webs as it is being slightly beyond the delivery point of the formed locally in the vat abi't'uminous emulboard, theemlsion will be the prepondersion substantially devoidr'oftibre.

ing element of the web. In other words, 2. A, process of making water-proof there will be more emulsion than fibrous paper, consisting in forming a plurality of 1 stock.

fibrous webs on a paper machine, and ap- The object ofithe operation just described plying to' one of 'sald webs as it is'being is to produce as near as possible a fibreless' formed locally a water-proofing agent in a film of bituminous or .pitchy material on the non-adhesive emulsified form; I

top of the web or ply bein'gfformed on the 3.A process of making water-proof paper, mould 6. As the web w contacts with the consisting in forming a fibrous web on the blanket; carrying on its under side the pricylinder mould "of a paper machine, conmary web w, the twoare united and pass tinuously applying a 'water proofing agent beneath thecouch roll 13. substantially devoid of fibre to a localized From the couch rolls the multiply sheet portion of the t' ormationtoform a superasses over the usual suction box 14 to tacillicial film; I

itate the removal of the water, and thence 4. A process of makingwater-proof paper,

to the usual press-rolls 15. consisting in forming a plurality of fibrous When the webs in question are finally webs on a paper machine, and'applying to passed over the paper machine a-nd the water one of said websv asit is being formed local-' has been removed, there is produced a mully, a waterproof pitch in an aqueous vehicle tiply sheet in which the plies are integrally substantially devoid of fibre.-

united by means of a continuous film of bi- J 5. A recess of making water-proof paper, tuminous or pitchy material and a film consisting in forming a plurality of fibrous whichis practically devoid of fibre. In other webs on a' paper machine and applying to words, thls continuous waterproof film being one of said webs as it is being withdrawn largely devoid of fibre has no pores through rrom the forming vat, a Water-proofing 1 wh ch air can'p'ass, as would be the case were agent in an aqueous vehicle.

I the waterproofing material mixed with a 6. A process 0 larger,am0unt of fibre stock.

if making waterrproof paper,

' We have heretofore referred to the fact cylinder mould of a paper machine, conthat there is an increasing local concentratinuously applying a wat'er-proofingagent j tion oi the emulsion with the fibrous stock' in the form of asubstantially fibreless film to p as the mould passes fromthe point I) to the a localized portion of the formation, and

int 0. For example, at thepoint b, the causing an upward flow of the water-proofs percentage of waterproofing medium with ing agent so as to carry said agent. forwardly i relation to the stock may be 10% whereas with the mould. at the pointc," the amount of bitumen or 1 v 4 pitch may be five times the amount of stock, THOMAS W. MORSE.

, representing a this point a saturation of I 'LESTERHKIRSGHBRAUN.

consisting in forming a fibrous web on the- 

